Metagenomic and targeted metabolomic analyses reveal distinct phenotypes of the gut microbiota in patients with colorectal cancer and type 2 diabetes mellitus

Background:Type 2 diabetes mellitus(T2DM)is an independent risk factor for colorectal cancer(CRC),and the patients with CRC and T2DM have worse survival.The human gut microbiota(GM)is linked to the development of CRC and T2DM,respectively.However,the GM characteristics in patients with CRC and T2DM remain unclear.Methods:We performed fecal metagenomic and targeted metabolomics studies on 36 samples from CRC patients with T2DM(DCRC group,n=12),CRC patients without diabetes(CRC group,n=12),and healthy controls(Health group,n=12).We analyzed the fecal microbiomes,characterized the composition and function based on the metagenomics of DCRC patients,and detected the short-chain fatty acids(SCFAs)and bile acids(BAs)levels in all fecal samples.Finally,we performed a correlation analysis of the differential bacteria and metabolites between different groups.Results:Compared with the CRC group,LefSe analysis showed that there is a specific GM community in DCRC group,including an increased abundance of Eggerthella,Hungatella,Peptostreptococcus,and Parvimonas,and decreased Butyricicoccus,Lactobacillus,and Paraprevotella.The metabolomics analysis results revealed that the butyric acid level was lower but the deoxycholic acid and 12-keto-lithocholic acid levels were higher in the DCRC group than other groups(P<0.05).The correlation analysis showed that the dominant bacterial abundance in the DCRC group(Parvimonas,Desulfurispora,Sebaldella,and Veillonellales,among others)was negatively correlated with butyric acid,hyodeoxycholic acid,ursodeoxycholic acid,glycochenodeoxycholic acid,chenodeoxycholic acid,cholic acid and glycocholate.However,the abundance of mostly inferior bacteria was positively correlated with these metabolic acid levels,including Faecalibacterium,Thermococci,and Cellulophaga.Conclusions:Unique fecal microbiome signatures exist in CRC patients with T2DM compared to those with non-diabetic CRC.Alterations in GM composition and SCFAs and secondary BAs levels may promote CRC development.

Current status of surgical treatment of rectal cancer in China

With the changing lifestyle and the acceleration of aging in the Chinese population,the incidence and mortality of colorectal cancer(CRC)have risen in the last decades.On the contrary,the incidence and mortality of CRC have continued to decline in the USA since the 1980s,which is mainly attributed to early screening and standardized diagnosis and treatment.Rectal cancer accounts for the largest proportion of CRC in China,and its treatment regimens are complex.At present,surgical treatment is still the most important treatment for rectal cancer.Since the first Chinese guideline for diagnosis and treatment of CRC was issued in 2010,the fourth version has been revised in 2020.These guidelines have greatly promoted the standardization and internationalization of CRC diagnosis and treatment in China.And with the development of comprehensive treatment methods such as neoadjuvant chemoradiotherapy,targeted therapy,and immunotherapy,the post-operative quality of life and prognosis of patients with rectal cancer have improved.We believe that the inflection point of the rising incidence and mortality of rectal cancer will appear in the near future in China.This article reviewed the current status and research progress on surgical therapy of rectal cancer in China.

Identifying Supercooled Liquid Water in Cloud Based on Airborne Observations: Correlation of Cloud Particle Number Concentration with Icing Probability and Proportion of Spherical Particles

Identifying supercooled liquid water(SLW)in clouds is critical for weather modification,aviation safety,and atmospheric radiation calculations.Currently,aircraft identification in the SLW area mostly depends on emprical estimation of cloud particle number concentration(N_(c))in China,and scientific verification and quantitative identification criteria are urgently needed.In this study,the observations are from the Fast Cloud Droplets Probe,Rosemount ice detector(RICE),and Cloud Particle Imager(CP_(i))onboard a King Air aircraft during seven flights in 2018 and 2019 over central and eastern China.Based on this,the correlation among N_(c),the proportion of spherical particles(P_(s)),and the probability of icing(P_(i))in supercooled stratiform and cumulus-stratus clouds is statistically analyzed.Subsequently,this study proposes a method to identify SLW areas using N_(c) in combination with ambient temperature.The reliability of this method is evaluated through the true skill statistics(TSS)and threat score(TS)methods.Numerous airborne observations during the seven flights reveal a strong correlation among Nc,P_(s),and P_(i)at the temperature from 0 to−18°C.When Nc is greater than a certain threshold of 5 cm^(−3),there is always the SLW,i.e.,P_(i)and P_(s)are high.Evaluation results demonstrate that the TSS and TS values for Nc=5 cm^(−3)are higher than those for Nc<5 cm^(−3),and a larger Nc threshold(>5 cm^(−3))corresponds to a higher SLW identification hit rate and a higher SLW content.Therefore,Nc=5 cm^(−3)can be used as the minimum criterion for identifying the SLW in clouds at temperature lower than 0°C.The SLW identification method proposed in this study is especially helpful in common situations where aircraft are equipped with only Nc probes and without the CP_(i)and RICE.

Coronavirus disease 2019 pandemic:what does wearing masks mean?

After the outbreak of coronavirus disease 2019(COVID-19),different measures have been taken to control the spread of the epidemic.Most international organizations,countries/regions have issued epidemic prevention guidelines or administrative guidelines,in which citizens are advised to pay attention to personal hygiene(such as washing hands frequently,covering the nose and mouth when sneezing),maintain social distance,and avoid gathering activities,and so on.[1]However,it is noted that instructions on whether citizens need to wear masks and when to wear masks are inconsistent across various countries.